In the course of a lifetime, cancer will strike about one in three women and one in two men. More than 560,000 die from it each year in the United States alone. Early detection and treatment is currently the leading method to reduce cancer death, especially if the cancer is detected before metastasis. For nearly all types of cancer, the 5-year relative survival rate is substantially lower if the disease is caught at an advanced stage. Moreover, the financial costs of cancer treatment at an advanced stage can be an additional burden. By 2020, the cost of cancer treatment is expected to be $207 billion annually in the United States. Accordingly, early detection of cancer is important for increasing cancer survival rates and reducing the cost of treatment.
However, methods for early detection often lack sensitivity and generate numerous false positives, leading to additional unnecessary testing, which can include biopsies and other painful, stressful and expensive procedures. As a result, the overall health burden borne by test subjects who register as false positives can outweigh the benefits to those patients who benefit from early detection of their cancers. This is especially true for screening tests where the incidence of disease is low. Thus, there is a need for a cancer diagnostic test which produces an unambiguous result, is low cost and minimally invasive, and has few false positives. Such a test would be useful for recurrence testing, validation testing, and other situations where an initial indication of cancer needs to be verified before an expensive and aggressive follow up procedure is performed.